One proposed structure of a vehicle has an engine configured to output power for driving the vehicle and an exhaust gas recirculation (EGR) system configured to circulate a part of exhaust from the engine into a gas intake line of the internal combustion engine. The proposed vehicle is driven only with output power of the engine (see, for example, Patent Document 1). This proposed vehicle makes a malfunction diagnosis of the exhaust gas recirculation system during decrease in speed and a fuel cut of the engine. Therefore the proposed vehicle enables restraint of torque shock by variation of ignition in comparison with a vehicle that makes the malfunction diagnosis of the exhaust gas recirculation during steady operation of the engine.    Patent Document 1: Japanese Patent Laid-Open No. H9-144609